Shares of WebMD Health Corp tumbled more than 24% in premarket trading Tuesday after the company lowered its 2012 outlook and ended discussions of being acquired.

The healthcare information provider said revenue may be as much as 2% to 8% lower than 2011 revenue, with revenues declining more in the first half of the year and improving in the second half of the year, according to a press release.

The company said it has terminated discussions of being acquired.

Back in October, Soros had disclosed a 5.6% stake in the company. He increased that stake just a few days ago, according to the 13G regulatory filing.

What's more is he's not the only legendary investor who has a sizable position in the company. Carl Icahn holds a 7.99% stake in the company, according to Bloomberg data citing a November 25, 2011 13D regulatory filing.